grit size / comparison of grits

cityjim · Jul 25, 2009

Here is the abrasive chart I stumbled on over at SRP . Later losing it and was found again by a fellow B&B shaver .

This will explain why I'm I'm getting such a clean comfortable shave with the Spyderco 306UF .

Notice the Norton 4/8K stones converts to only 1,100 ANSI (USA) grit at the Norton 4k level . The Norton 8K converts to 1,500 ANSI (USA) grit . Explaining why the Spyderco 306UF gives a much sharper cleaner edge . The Spyderco 306UF is rated at 2,000 ANSI (USA) grit per Spyderco .

The Shapton 16K only compares at say 2,100 or 2,200 ANSI (USA) grit . Possibly equivalent to the Spyderco 306UF .

Seems like all the stone slash sharpener makers use their own "grit" scale . Only comparison standard we can follow is the micron standard .

So using the micron standard we see this :

Spyderco 306UF at 1 micron

Norton 4K at 6 microns
Norton 8K at 3 microns

Shapton 16K at 0.92 micron
Shapton 30K at 0.49 micron

Smokintbird at SRP complied this

http://www.straightrazorplace.com/f...25111-grit-sizes-grit-comparison-07-23-09.pdf

http://www.straightrazorplace.com/forums/advanced-honing-topics/38702-grit-sizes-3.html

cityjim

English · Aug 4, 2009

Great information CityJim, thanks for posting all of this. I found it very interesting and informative.

I have used natural stones until recently and grit sizes didn't always help me.

I tried the spyderco ultrafine some three years ago. At that time, I shaved off a coticule. I thought the ultrafine gave a marginal improvement. But I stuck with the coticule which on occasion and when everything was just right would give a perfect edge for me at least. I am sure the spyderco ultrafine is sharper but I'm not sure about it being smoother. But that might be down to my honing skills. :wink:

Three years on, I have now tried many many hones and I have a Charnley Forest and a couple of the Japanese Honyama quarry finishing hones which are both very fine grit and put a very sharp edge on a blade. The Charnley is the sharper, but the Honyama gives the smoother shave. At a lesser level of sharpness I also have a green/blue coloured Escher which delivers a comfortable shave. It's delivers a very smooth edge.

What I have found is that smoothness often comes at the expense of blade shaving life between honings. Not that this really matters all that much if you can hone your own blade. The other thing I have found is that for me at least, a razors edge can be too sharp in the same way that the Feather DE razor is considered by many to be too sharp.

Today I use a synthetic Japanese hone rated at 8000 grit and I assume that to be the new Japanese standard. However I have tried other japanese hones which are rated higher on the box but the shaving edge is neither as sharp or as comfortable as the the one I use (for me at least). I have also read that in Japan there is no recognised measure beyond the 8000 level. In Japan by putting 8000 grit on the box, they are saying this is their best. I don't have a clue were Naniwa get their 10,000 and 12,000 ratings from for example. But as an example, they don't give a better edge than my 8K.

Another interesting thing I have discovered is that the softer hones work better with the harder steels. It's because the softer material release more new cutting material than the harder stones. It is for this reason that many natural fine grit hones are not as effective on the harder steels. It also explains why some struggle to get a good edge on a Chinese 12k which is a particularly hard stone.

Stainless steel razors from Friodur and the higher rockwell hardened Thiers Issard razors prefer a soft hone. I suspect the harder steel would hone better on an Escher than a coticule for example. Interestingly, King do two top of range 8K hones for this very reason. One is soft and one is normal. The soft is designed for harder steel. I think that King hones are often criticised for being two soft and needing regular lapping. I think that is just lack of knowledge.

I have 10K Chosera from Naniwa which I originally thought was harder than the Naniwa Superstone. I thought this because it did a better job on the harder steel razors. In actual fact it is a softer hone and that is why it does a better job on the hard steels. It is also why it works well on many kitchen knives which generally have hard edges.The Naniwa Chosera range of hones work better with hard steel than say the Naniwa Superstone range which works well with most carbon steel razors. The Japanese in particular are very precise at having the right tool for the job and that is why they produce so many types of synthetic hones. Unfortunately they don't seem to know how to explain these differences very well to their Western customers.

So for many DIY honers, if you have a hard steel and soft steel blades, you may need two sets of hones to optimise the edges.

All good news for the guys with HAD.

Tolduonce · Aug 4, 2009

Excellent information CityJim and English. Can't argue with stardization. For the sake of better information, what steels are considered "hard" and which ones "soft"? All of my razors are carbon and I don't intend to ever go with SS. How would you categorize Solingen steel, W&B, Original Pipe? What about Dovo? Thanks to both of you for helping to enlighten me.

English · Aug 5, 2009

Tolduonce said:
Excellent information CityJim and English. Can't argue with stardization. For the sake of better information, what steels are considered "hard" and which ones "soft"? All of my razors are carbon and I don't intend to ever go with SS. How would you categorize Solingen steel, W&B, Original Pipe? What about Dovo? Thanks to both of you for helping to enlighten me.

Solingen steel is generally a soft carbon steel.
Sheffield steel is softer. W&B and Original Pipe are both from Sheffield.

Steel from Sweden is often harder. Stainless steel is generally harder and much of the production from France is (although often Sheffield steel) tempered to a hard edged finish.

Dovo use steel from Solingen, stainless steels and steel from Sweden. They have a mixed bag of hard and soft steels.

Correctly honed, you really shouldn't be able to tell the differences. But for the honer, it is hard work to try to sharpen the harder steel edges with the wrong hones and if a razor is not responding it is usually because the hone is to hard for the edge being honed.

sol92258 · Aug 5, 2009

and here I was thinking this would be a thread about breakfast...

Tolduonce · Aug 5, 2009

English said:
Solingen steel is generally a soft carbon steel.
Sheffield steel is softer. W&B and Original Pipe are both from Sheffield.

Steel from Sweden is often harder. Stainless steel is generally harder and much of the production from France is (although often Sheffield steel) tempered to a hard edged finish.

Dovo use steel from Solingen, stainless steels and steel from Sweden. They have a mixed bag of hard and soft steels.

Correctly honed, you really shouldn't be able to tell the differences. But for the honer, it is hard work to try to sharpen the harder steel edges with the wrong hones and if a razor is not responding it is usually because the hone is to hard for the edge being honed.

Thanks. So much to remember so little free braindisk space left. :001_smile

leighton · Aug 5, 2009

English said:
Correctly honed, you really shouldn't be able to tell the differences. But for the honer, it is hard work to try to sharpen the harder steel edges with the wrong hones and if a razor is not responding it is usually because the hone is to hard for the edge being honed.

I I.D. Stainless steel by how freaking hard it is to remove metal. :lol: